Why do thermodynamics and fluid dynamics overwhelm me?

You sit down to study and the whole subject rises up at once — every equation, every unsolved problem set, every gap you haven't closed. You feel small in the chair. This is not weakness. It is what happens when you try to see a mountain whole instead of looking at the next step. No one holds thermodynamics in their mind all at once. Not your professor, not the person who wrote your textbook. They hold one problem, then the next. You are comparing your scattered attention to their trained focus and calling the difference proof of your unfitness. It is not. It is only proof you have not yet trained your attention the way they trained theirs. If the weight of this follows you outside your desk — into your sleep, your appetite, your sense of yourself — that is worth saying to someone who can help you carry it. That is not a failure of will. It is simply a different problem than the one this page can solve.